/*
 * HomeLight.java 12 mars 2009
 *
 * Sweet Home 3D, Copyright (c) 2009 Emmanuel PUYBARET / eTeks <info@eteks.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package com.eteks.sweethome3d.model;

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.io.IOException;
import java.io.ObjectInputStream;

/**
 * A light in {@linkplain Home home}.
 * @author Emmanuel Puybaret
 * @since  1.7
 */
public class HomeLight extends HomePieceOfFurniture implements Light
{
	private static final long serialVersionUID = 1L;
	
	/**
	 * The properties of a light that may change. <code>PropertyChangeListener</code>s added 
	 * to a light will be notified under a property name equal to the string value of one these properties.
	 */
	public enum Property
	{
		POWER
	};
	
	private final LightSource[] lightSources;
	private float power;
	
	private transient PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);
	
	/**
	 * Creates a home light from an existing one.
	 * @param light the light from which data are copied
	 */
	public HomeLight(Light light)
	{
		super(light);
		this.lightSources = light.getLightSources();
		this.power = 0.5f;
	}
	
	/**
	 * Initializes transient fields to their default values 
	 * and reads light from <code>in</code> stream with default reading method.
	 */
	private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException
	{
		// Let power to 0 for lights previously added to home 
		this.propertyChangeSupport = new PropertyChangeSupport(this);
		in.defaultReadObject();
	}
	
	/**
	 * Adds the property change <code>listener</code> in parameter to this piece.
	 * @since 3.0
	 */
	@Override
	public void addPropertyChangeListener(PropertyChangeListener listener)
	{
		this.propertyChangeSupport.addPropertyChangeListener(listener);
		super.addPropertyChangeListener(listener);
	}
	
	/**
	 * Removes the property change <code>listener</code> in parameter from this piece.
	 * @since 3.0
	 */
	@Override
	public void removePropertyChangeListener(PropertyChangeListener listener)
	{
		this.propertyChangeSupport.removePropertyChangeListener(listener);
		super.removePropertyChangeListener(listener);
	}
	
	/**
	 * Returns the sources managed by this light. Each light source point
	 * is a percentage of the width, the depth and the height of this light.  
	 * with the abscissa origin at the left side of the piece,
	 * the ordinate origin at the front side of the piece
	 * and the elevation origin at the bottom side of the piece.
	 * @return a copy of light sources array.
	 */
	public LightSource[] getLightSources()
	{
		if (this.lightSources.length == 0)
		{
			return this.lightSources;
		}
		else
		{
			return this.lightSources.clone();
		}
	}
	
	/**
	 * Returns the power of this light.
	 * @since 3.0
	 */
	public float getPower()
	{
		return this.power;
	}
	
	/**
	 * Sets the power of this light. Once this light is updated, 
	 * listeners added to this piece will receive a change notification.
	 * @since 3.0
	 */
	public void setPower(float power)
	{
		if (power != this.power)
		{
			float oldPower = this.power;
			this.power = power;
			this.propertyChangeSupport.firePropertyChange(Property.POWER.name(), oldPower, power);
		}
	}
	
	/**
	 * Returns a clone of this light.
	 */
	@Override
	public HomeLight clone()
	{
		HomeLight clone = (HomeLight) super.clone();
		clone.propertyChangeSupport = new PropertyChangeSupport(clone);
		return clone;
	}
}
